Recommend several e-books and documents to find addresses

1. Books on society, philosophy, humanities and business https://ebook2.lorefree.com/

2. Collection of several popular e-book websites https://xmsoushu.com/#/

3. All periodicals and magazines in China (all before the current quarter) https://m.fx361.com/

4. The world's largest PDF download website with many English books https://www.pdfdrive.com/

5. Books, papers, ancient books, documents https://www.toplinks.cc/s/

6. Currently the best ancient book sorting and storage website, I really like https://new.shuge.org/

7. The world's largest digital library https://zh.b-ok.cc/

8. Gutenberg Book Project, English book and literature search https://www.gutenberg.org/